AXISYMMETRY OF MANTLE ASPHERICAL STRUCTURES

被引:8
作者
MATYSKA, C
机构
[1] Department of Geophysics, Charles University, Prague
关键词
D O I
10.1029/94GL03218
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
Recent seismic tomographic models have revealed broad, low velocity anomalies in the lower mantle beneath Africa and the central Pacific that correspond to the poles of the surface geotectonic reference network. We test the hypothesis that the tomographic models are axisymmetrical with respect to axes passing near the geotectonic poles. The symmetry is apparent at the bottom of the lower mantle as well as in the transition zone in the upper mantle. This supports the idea of massive flushing of cold upper mantle material into the bottom part of the lower mantle and points to a stabilizing role of the lower mantle megaplumes on whole mantle processes.
引用
收藏
页码:521 / 524
页数:4
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